please help me I don't understand this and my support Facilitator TEACHER was bot here today

We have the following:
The domain of a function f (x) is the set of all values for which the function is defined, and the range of the function is the set of all values that f takes.
In other words, the range is the output values or the values that can take y.
Therefore, the answer is:
[tex]R=0\leq y\leq8[/tex]